3 files changed, 17 insertions, 10 deletions

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 4d6f2fe1cfe9..9230402c45af 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1656,6 +1656,10 @@ static int sg_start_req(Sg_request *srp, unsigned char *cmd)
                 md->nr_entries = req_schp->k_use_sg;
                 md->offset = 0;
                 md->null_mapped = hp->dxferp ? 0 : 1;
+                if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
+                        md->from_user = 1;
+                else
+                        md->from_user = 0;
         }
 
         if (iov_count) {
diff --git a/fs/bio.c b/fs/bio.c
index 1486b19fc431..76738005c8e8 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -705,14 +705,13 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
 }
 
 static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
-                          struct sg_iovec *iov, int iov_count, int uncopy,
-                          int do_free_page)
+                          struct sg_iovec *iov, int iov_count,
+                          int to_user, int from_user, int do_free_page)
 {
         int ret = 0, i;
         struct bio_vec *bvec;
         int iov_idx = 0;
         unsigned int iov_off = 0;
-        int read = bio_data_dir(bio) == READ;
 
         __bio_for_each_segment(bvec, bio, i, 0) {
                 char *bv_addr = page_address(bvec->bv_page);
@@ -727,13 +726,14 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
                         iov_addr = iov[iov_idx].iov_base + iov_off;
 
                         if (!ret) {
-                                if (!read && !uncopy)
-                                        ret = copy_from_user(bv_addr, iov_addr,
-                                                             bytes);
-                                if (read && uncopy)
+                                if (to_user)
                                         ret = copy_to_user(iov_addr, bv_addr,
                                                            bytes);
 
+                                if (from_user)
+                                        ret = copy_from_user(bv_addr, iov_addr,
+                                                             bytes);
+
                                 if (ret)
                                         ret = -EFAULT;
                         }
@@ -770,7 +770,8 @@ int bio_uncopy_user(struct bio *bio)
 
         if (!bio_flagged(bio, BIO_NULL_MAPPED))
                 ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs,
-                                     bmd->nr_sgvecs, 1, bmd->is_our_pages);
+                                     bmd->nr_sgvecs, bio_data_dir(bio) == READ,
+                                     0, bmd->is_our_pages);
         bio_free_map_data(bmd);
         bio_put(bio);
         return ret;
@@ -875,8 +876,9 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
         /*
          * success
          */
-        if (!write_to_vm && (!map_data || !map_data->null_mapped)) {
-                ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0);
+        if ((!write_to_vm && (!map_data || !map_data->null_mapped)) ||
+            (map_data && map_data->from_user)) {
+                ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 1, 0);
                 if (ret)
                         goto cleanup;
         }
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index bb3d39978701..0146e0fecf1a 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -723,6 +723,7 @@ struct rq_map_data {
         int nr_entries;
         unsigned long offset;
         int null_mapped;
+        int from_user;
 };
 
 struct req_iterator {